# ---- In-source guard ----

if (CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR)
    message(
            FATAL_ERROR
            "In-source builds are not supported. "
            "Please read the BUILDING document before trying to build this project. "
            "You may need to delete 'CMakeCache.txt' and 'CMakeFiles/' first."
    )
endif ()
